Autonomous vehicle speed control device

ABSTRACT

An autonomous vehicle is provided with a touch panel that enables an operator to input vehicle speed control instructions during an automatic driving mode and a mechanical operation unit for inputting driving control instructions. When the driving mode of the autonomous vehicle is the automatic driving mode or a semi-automatic driving mode, a driving control unit of the autonomous vehicle prioritizes a vehicle speed control instruction input from the touch panel over a vehicle speed control instruction input from the mechanical operation unit and executes vehicle speed control for the autonomous vehicle based on the prioritized instruction.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No. 2019-121400 filed on Jun. 28, 2019, which is incorporated herein by reference in its entirety including the specification, claims, drawings, and abstract.

TECHNICAL FIELD

The present description discloses an autonomous vehicle speed control device.

BACKGROUND

Autonomous vehicles capable of performing automatic driving are conventionally known. Automatic driving means that a computer executes at least a part of various driving controls including vehicle speed control and steering control. Generally, autonomous vehicles are operable in a plurality of driving modes, which include an automatic driving mode for performing automatic driving and a manual driving mode for enabling an operator in the autonomous vehicle to perform driving control.

It is conventionally known that, even in the automatic driving mode, an operator in an autonomous vehicle may want to control the vehicle speed of the autonomous vehicle, and there has been a case of providing a mechanical operation unit in an autonomous vehicle for enabling the operator to perform vehicle speed control in the automatic driving mode. The mechanical operation unit is not a foot-operated pedal such as an accelerator pedal or a brake pedal provided in conventional automotive vehicles, and is provided higher than a seat surface of an operator's seat to enable the operator to operate the unit by hand.

For example, JP 2018-136714 A discloses an autonomous vehicle capable of performing autonomous driving, in which a mechanical operation unit (a joystick) is provided for enabling manual operation by an operator to perform vehicle speed control in the automatic driving mode.

Incidentally, it is conceivable that the operator may use a touch panel to perform vehicle speed control for the autonomous vehicle in the automatic driving mode. For example, the touch panel displays a vehicle speed control button so that the operator can operate this button to realize the vehicle speed control. Since the burden on the operator can be reduced during the automatic driving mode, it becomes easy for the operator to visually recognize information displayed on the touch panel. Therefore, performing the vehicle speed control using the touch panel makes it easy to grasp the information (for example, vehicle information, environmental information, and message from outside the vehicle) displayed on the touch panel.

On the other hand, the operator may manually drive the autonomous vehicle in a mode other than the automatic driving mode (for example, during the manual driving mode). When the operator performs manual driving, operation using the mechanical operation unit is considered to be desirable rather than operation using the touch panel, because not only the vehicle speed control but also various operations including a handling control are required. Accordingly, it is considered desirable for the autonomous vehicle to be provided with the mechanical operation unit in addition to the touch panel.

As described above, when the autonomous vehicle is equipped with the touch panel for performing vehicle speed control in the automatic driving mode and the mechanical operation unit for performing driving control, if the mode currently selected is the automatic driving mode, it is assumed that the operator intends to perform vehicle speed control operations using the touch panel. In such a situation, if the operator unintentionally operates the mechanical operation unit while operating the touch panel, or if another occupant operates the mechanical operation unit while the operator is operating the touch panel, speed controls not intended by the operator may be performed.

An autonomous vehicle speed control device disclosed in the present description is applicable to an autonomous vehicle that is equipped with a touch panel for performing vehicle speed control operations in the automatic driving mode and is further equipped with a mechanical operation unit for performing vehicle speed control operations, and intends to suppress performance of vehicle speed controls not intended by an operator in the automatic driving mode.

SUMMARY

The autonomous vehicle speed control device disclosed in the present description is an autonomous vehicle speed control device provided in an autonomous vehicle capable of driving in a plurality of modes including an automatic driving mode for performing automatic driving, including

a touch panel on which a vehicle speed control button for inputting a vehicle speed control instruction to the autonomous vehicle is displayed,

a mechanical operation unit provided higher than a seat surface of a seat of the autonomous vehicle and configured to input a vehicle speed control instruction to the autonomous vehicle by manual operation, and

a vehicle speed control unit configured to control the vehicle speed of the autonomous vehicle by prioritizing the vehicle speed control instruction input from the touch panel over the vehicle speed control instruction input from the mechanical operation unit, in the automatic driving mode.

According to the above-mentioned configuration, in the case of operation in the automatic driving mode, when an operator performs the vehicle speed control using the touch panel, the vehicle speed control instruction input from the touch panel is prioritized over the vehicle speed control instruction input from the mechanical operation unit even when the mechanical operation unit is operated. Therefore, performance of a vehicle speed control not intended by the operator can be suppressed.

A mechanical emergency-stop operation unit for inputting a stop instruction to the autonomous vehicle may be further provided, and the vehicle speed control unit may cause the autonomous vehicle to stop by prioritizing the stop instruction input from the emergency stop operation unit over the vehicle speed control instructions input from the touch panel and the mechanical operation unit.

In the automatic driving mode, the vehicle speed control unit may prioritize a deceleration control instruction input from the touch panel over the vehicle speed control instruction input from the mechanical operation unit and cause the autonomous vehicle to decelerate.

The mechanical operation unit may be storable in a storage part covered with a lid. In the automatic driving mode, it is desirable that the vehicle speed control unit invalidates the vehicle speed control instruction from the mechanical operation unit.

It may be the case that a foot-operated pedal for inputting a vehicle speed control instruction to the autonomous vehicle is not provided.

According to the autonomous vehicle speed control device described in the present description, the autonomous vehicle is equipped with the touch panel for performing vehicle speed control operations in the automatic driving mode and is further equipped with the mechanical operation unit for performing vehicle speed control operations, and can suppress performance of vehicle speed controls not intended by an operator in the automatic driving mode.

BRIEF DESCRIPTION OF DRAWINGS

Embodiment(s) of the present disclosure will be described based on the following figures, wherein:

FIG. 1 is an external view illustrating an autonomous vehicle according to the present embodiment;

FIG. 2 is a first perspective diagram illustrating the interior of a passenger compartment of the autonomous vehicle according to the present embodiment;

FIG. 3 is a second perspective diagram illustrating the interior of the passenger compartment of the autonomous vehicle according to the present embodiment;

FIG. 4 is a diagram illustrating an exemplary screen of a touch panel to be displayed when the vehicle is stopped;

FIG. 5 is a diagram illustrating an exemplary screen of the touch panel to be displayed at the time of automatic traveling;

FIG. 6 is a perspective diagram illustrating a mechanical operation unit; and

FIG. 7 is a functional block diagram illustrating a driving control device according to the present embodiment.

DESCRIPTION OF EMBODIMENTS

FIG. 1 is an external view illustrating an autonomous vehicle 10 according to the present embodiment. In each drawing of the present description, the terms “front (FR)” and “rear” indicate front and rear in the longitudinal direction of the vehicle, and the terms “left (LH)” and “right” indicate left and right when facing forward, and “up (UP)” and “down” indicate up and down in the vertical direction of the vehicle.

The autonomous vehicle 10 is a substantially rectangular parallelepiped and has a shape symmetrical in the front-rear direction, and an appearance design thereof is symmetrical in the longitudinal direction. A pillar 12 extending in the vertical direction is provided at each of four corners in a plan view, and a wheel 14 is provided below each pillar 12. Most of front, rear, left, and right side walls of the autonomous vehicle 10 are semitransparent panels 16. Each panel 16 may be configured as a display panel, on which characters or the like can be displayed.

A part of the left side panel is constituted as a slidable door 18, so that an occupant can get on and off by sliding and opening the door 18. Although not illustrated in FIG. 1 , retractable ramp equipment configured to be taken out and in is stored below the door 18. The ramp equipment can be used for loading and unloading a wheelchair or the like.

Further, the autonomous vehicle 10 is a vehicle capable of performing autonomous driving. Specifically, the autonomous vehicle 10 is configured to perform driving in a plurality of driving modes including an automatic driving mode, a semi-automatic driving mode, and a manual driving mode.

The automatic driving mode is a driving mode in which a computer (serving as a driving control unit (described below)) mounted on the autonomous vehicle 10 performs most of driving control. In the present description, the driving control is a concept including shift change control, vehicle speed control, and steering control. Further, the vehicle speed control is also a concept including start control, stop control, and acceleration/deceleration control for the autonomous vehicle 10. The autonomous vehicle 10 is configured to be able to communicate with a management center that manages and controls a plurality of autonomous vehicles 10. In the automatic driving mode, the autonomous vehicle 10 travels along a predetermined route under the control of the management center. In the automatic driving mode, the computer performs the driving control according to driving instructions from the management center. However, the start control performed in a stop state requires an operation by an operator in the autonomous vehicle 10.

The semi-automatic driving mode is a driving mode similar to the automatic driving mode in that the computer mounted on the autonomous vehicle 10 performs most of the driving control for the autonomous vehicle 10. In the semi-automatic driving mode, without depending on instructions from the management center, the computer performs driving control based on detection results obtained by various sensors (for example, a camera or a lidar) provided on the autonomous vehicle 10, and travels along a predetermined route. However, even in the semi-automatic driving mode, the start control performed in a stop state requires an operation by an operator in the autonomous vehicle 10.

The manual driving mode is a mode in which the autonomous vehicle 10 does not perform autonomous driving and an operator in the autonomous vehicle 10 performs driving control for the autonomous vehicle 10.

The autonomous vehicle 10 is a shared vehicle for riding by an unspecified large number of occupants. In the present embodiment, the autonomous vehicle 10 is used as a bus that carries passengers while traveling along a predetermined route in a specific site. Accordingly, the autonomous vehicle 10 is supposed to repeat stopping and starting relatively frequently. Further, the autonomous vehicle 10 is supposed to travel relatively slowly (e.g., at 30 km/h or less).

However, the usage form of the autonomous vehicle 10 disclosed in the present description is appropriately changeable. For example, the autonomous vehicle 10 may be used as a movable business space, or as a shop such as a retail shop that displays and sells various commodities or as a restaurant that cooks and provides food and drink. Further, as another form, the autonomous vehicle 10 may be used as an office for various types of office work, meeting with customers, and the like. Further, the use scene of the autonomous vehicle 10 is not limited to business use. For example, the autonomous vehicle 10 may be used as personal transportation means. Further, the traveling pattern or the traveling speed of the autonomous vehicle 10 may be changed appropriately.

The autonomous vehicle 10 is an electric vehicle having, as a prime mover, a driving motor that receives power supply from batteries. Each battery is a secondary battery configured to be chargeable and dischargeable, and is periodically charged by an external power source. The autonomous vehicle 10 is not limited to the electric vehicle and may be another type of vehicle. For example, the autonomous vehicle 10 may be a vehicle equipped with an engine (e.g., an internal combustion engine) serving as a prime mover, or may be a hybrid vehicle equipped with both an engine and a driving motor each serving as a prime mover. Further, the autonomous vehicle 10 may be a hydrogen fueled vehicle that drives a driving motor with electric power generated by fuel cells.

FIGS. 2 and 3 are perspective diagrams illustrating the interior of a passenger compartment of the autonomous vehicle 10. As mentioned above, since the autonomous vehicle 10 is used as a bus, the passenger compartment includes a central part configured as a floor 20 available for standing occupants or wheelchaired occupants. Further, occupant seats 22 are provided along sidewalls in the passenger compartment.

The autonomous vehicle 10 includes an operator seat 24 provided for an operator who controls driving of the autonomous vehicle 10 and operates each device (such as an air conditioner or windshield wipers) provided in the autonomous vehicle 10. FIG. 2 illustrates a state where a seat body 24 a of the operator seat 24 is reclined so that a seat surface 24 b appears. The seat body 24 a is configured to be flipped up. In the present embodiment, the operator seat 24 is provided on the left side in the passenger compartment and adjacent to the front side of the door 18, although the operator seat 24 may be provided on the right side in the passenger compartment.

An armrest 26 extending in the front-rear direction to enable an operator sitting on the operator seat 24 to place his/her arm is provided on the front side of the operator seat 24. As mentioned above, in the present embodiment, since the operator seat 24 is provided on the left side in the passenger compartment, the armrest 26 is disposed at the left end in the passenger compartment. If the operator seat 24 is provided on the right side in the passenger compartment, the armrest 26 is disposed at the right end in the passenger compartment. The armrest 26 is provided higher than the seat surface 24 b of the operator seat 24 in a reclined state.

A touch panel 28 standing upright from an upper surface of the armrest 26 is provided at a front end of the armrest 26 (see FIG. 3 ). The touch panel 28 faces the rear side (that is, the operator seat 24 side). Accordingly, the operator can manually operate the touch panel 28 while sitting on the operator seat 24 and placing his/her arm on the armrest 26. The touch panel 28 enables the operator to input a vehicle speed control instruction in the automatic driving mode and input a device control instruction to each device (blinkers, a horn, headlights, the air conditioner, the windshield wipers, and the like) provided in the autonomous vehicle 10. A display screen of the touch panel 28 will be described in detail below.

Further, a storage compartment 30 such as a console box, which can store a mechanical operation unit for inputting a driving control instruction to the autonomous vehicle 10, is provided in the armrest 26. The storage compartment 30 is covered with a lid 32. That is, when stored in the storage compartment 30 the mechanical operation unit is not exposed to the interior of the passenger compartment. In the present embodiment, the upper surface of the armrest 26 and the lid 32 are disposed on the same plane. In the present embodiment, although the storage compartment 30 is provided in the armrest 26, the storage compartment 30 may be provided in a place other than the armrest 26. Even in such a case, it is desirable that the storage compartment 30 is provided in an inconspicuous place, for example, at one of front, rear, left, and right ends in the interior of the passenger compartment. The storage compartment 30, the lid 32, and the mechanical operation unit will be described in detail below.

Further, a mechanical emergency-stop operation unit 34 for inputting an (emergency) stop instruction to the autonomous vehicle 10 is provided on the upper surface of the armrest 26. In the present embodiment, the emergency-stop operation unit 34 is a button.

The autonomous vehicle 10 is provided with the touch panel 28, the mechanical operation unit, and the emergency-stop operation unit 34, as only three operation devices for inputting vehicle speed control instructions to the autonomous vehicle 10. That is, the autonomous vehicle 10 is not provided with a foot-operated pedal for inputting a vehicle speed control instruction, such as an accelerator pedal or a brake pedal provided in conventional automotive vehicles or the like.

A display device 36 that displays information relating to the autonomous vehicle 10 is provided at a front left corner in the passenger compartment (see FIG. 3 ). The information displayed on the display device 36 includes, for example, vehicle speed of the autonomous vehicle 10, ambient temperature, and the next stop. Like the touch panel 28, the display device 36 faces the rear side so that the touch panel 28 and the display device 36 are disposed side by side when seen by the operator sitting on the operator seat 24. Thus, suitably, the operator can visually recognize both the touch panel 28 and the display device 36. The display device 36 and the touch panel 28 may be positioned at the same height. Specifically, the touch panel 28 and the display device 36 are disposed in such a manner that the upper edge of the display device 36 and the upper edge of the touch panel 28 are at the same height, the lower edge of the display device 36 and the lower edge of the touch panel 28 are at the same height, or the altitudinal center of the display device 36 and the altitudinal center of the touch panel 28 are at the same height.

FIGS. 4 and 5 illustrate exemplary screens to be displayed on the touch panel 28. FIG. 4 illustrates an exemplary screen displayed when the autonomous vehicle 10 is in the automatic driving mode and is stopped. FIG. 5 is an exemplary screen displayed when the autonomous vehicle 10 is in the automatic driving mode and is traveling.

First, with reference to FIG. 4 , when the autonomous vehicle 10 is in the automatic driving mode and is stopped, a GO button 40 serving as a vehicle speed control button for inputting a vehicle speed control instruction to the autonomous vehicle 10 is displayed on the touch panel 28. The GO button 40 is a button for inputting a start instruction to the autonomous vehicle 10. When the GO button 40 is operated, the autonomous vehicle 10 starts traveling (in the automatic driving mode, in this case).

Next, with reference to FIG. 5 , when the autonomous vehicle 10 is in the automatic driving mode and is traveling, a SLOWDOWN button 42 serving as a vehicle speed control button is displayed on the touch panel 28, instead of the GO button 40. The SLOWDOWN button 42 is a button for inputting a deceleration control instruction to the autonomous vehicle 10. When the SLOWDOWN button 42 is operated, the autonomous vehicle 10 decelerates. The SLOWDOWN button 42 may be repetitively operated to cause the autonomous vehicle 10 to stop as intended.

In the present embodiment, when the vehicle is traveling in the automatic driving mode, the vehicle speed control that the operator can input is only the deceleration control instruction. However, in addition to the SLOWDOWN button 42, a button for inputting an acceleration control instruction or a button for inputting a stop instruction may be displayed so that the operator can input the acceleration control instruction or the stop instruction. Needless to say, in the automatic driving mode, the autonomous vehicle 10 can automatically decelerate or stop according to instructions from the management center. When the autonomous vehicle 10 is stopped, the GO button 40 is displayed again, instead of the SLOWDOWN button 42, as illustrated in FIG. 4 .

Buttons displayed on the touch panel 28 include, in addition to the vehicle speed control button, driving mode buttons 44 for inputting driving mode change instructions, shift buttons 46 for inputting shift change control instructions, a P brake button 48 for inputting a motor-driven parking brake activation/release instruction, and various device control buttons for inputting device control instructions to devices provided in the autonomous vehicle 10. According to the examples illustrated in FIGS. 4 and 5 , blinker buttons 50 for controlling blinkers, a hazard button 52 for activating a hazard warning system, a horn button 54 for operating the horn, light buttons 56 for controlling headlights and taillights, an air conditioner tab 58 for controlling the air conditioner, and a windshield wiper tab 60 for controlling the windshield wipers are displayed as the device control buttons. When the air conditioner tab 58 is touched, various buttons for controlling the air conditioner are displayed. When the windshield wiper tab 60 is touched, various buttons for controlling the windshield wipers are displayed. The driving mode buttons 44 are operable only when the autonomous vehicle 10 is stopped. Further, in the present embodiment, the shift buttons 46 are not operable in the automatic driving mode, because shift change by an operator's operation is restricted.

Further, other information displayed on the touch panel 28 includes remaining battery level of the autonomous vehicle 10, opened/closed state of the door 18, state of the ramp equipment, and detection states of various sensors provided in the autonomous vehicle 10.

FIG. 6 illustrates a mechanical operation unit 70 pulled out of the storage compartment 30. The mechanical operation unit 70 has a stick shape and keeps an upright posture when stored in the storage compartment 30 so as to be raised in the vertical direction. Storing the mechanical operation unit 70 in the storage compartment 30 can prevent the operator from erroneously operating the mechanical operation unit 70 or prevent another occupant from operating the mechanical operation unit 70. The lid 32 may be configured to be locked so that occupants other than the operator cannot open the lid 32. Further, the space in the vehicle can be effectively used when the mechanical operation unit 70 is stored in the storage compartment 30.

When the operator opens the lid 32 and pulls out the mechanical operation unit 70 upward, the mechanical operation unit 70 becomes operable as illustrated in FIG. 6 . Alternatively, a switch may be provided in the storage compartment 30, so that the mechanical operation unit 70 automatically moves upward from the storage compartment 30 when the switch is operated. In the operable state, the mechanical operation unit 70 is in a state where it stands upright from the upper surface of the armrest 26. The mechanical operation unit 70 is provided higher than the seat surfaces of the seats in the autonomous vehicle 10. In particular, as described above, since the armrest 26 is provided higher than the seat surface 24 b of the operator seat 24 in the reclined state, it is obvious that the mechanical operation unit 70 is positioned higher than the seat surface 24 b in the reclined state.

The mechanical operation unit 70 is mainly pulled out of the storage compartment 30 when the driving mode of the autonomous vehicle 10 is the manual driving mode. When the driving mode of the autonomous vehicle 10 is the automatic driving mode or the semi-automatic driving mode, it is desirable that the mechanical operation unit 70 is stored in the storage compartment 30 so as to prevent erroneous operation of the mechanical operation unit 70.

The mechanical operation unit 70 is operable by hand. The mechanical operation unit 70 is a lever type that is manually operable. That is, the mechanical operation unit 70 is configured to be tiltable in the front, rear, left, and right directions with a lower edge thereof as a fulcrum. When the mechanical operation unit 70 is tilted forward, an acceleration control instruction can be input to the autonomous vehicle 10. When the mechanical operation unit 70 is tilted rearward, a deceleration control instruction can be input to the autonomous vehicle 10. Further, when the mechanical operation unit 70 is tilted leftward, a left-turn control instruction can be input to the autonomous vehicle 10. When the mechanical operation unit 70 is tilted rightward, a right-turn control instruction can be input to the autonomous vehicle 10.

Further, mechanical device control switches for inputting device control instructions to the devices provided in the autonomous vehicle 10 are provided at an upper part of the mechanical operation unit 70. In the present embodiment, switches for controlling the notification to the outside of the vehicle are provided as the device control switches. Specifically, blinker switches 72 for operating the blinkers and a horn switch 74 for activating the horn are provided. As described above, the mechanical operation unit 70 can be used not only when instructing the acceleration/deceleration control and the turning control but also when operating the blinkers and the horn. Needless to say, the device control switches on the mechanical operation unit 70 may include additional switches for controlling other devices.

In the present embodiment, the touch panel 28 is disposed at the front end of the armrest 26 and the mechanical operation unit 70 stands upright on the armrest 26. That is, the touch panel 28 and the mechanical operation unit 70 are disposed adjacently. In the present embodiment, even when the driving control is performed using the mechanical operation unit 70, the touch panel 28 is usable to operate the devices provided in the autonomous vehicle 10. Accordingly, since the touch panel 28 and the mechanical operation unit 70 are adjacent to each other, the operator can suitably operate both the touch panel 28 and the mechanical operation unit 70.

FIG. 7 is a functional block diagram illustrating a driving control device 80 provided on the autonomous vehicle 10. The driving control device 80 includes the touch panel 28, the emergency-stop operation unit 34, and the mechanical operation unit 70, which are described above, and is configured to further include a driving mode selection unit 82 and a driving control unit 84. The driving mode selection unit 82 and the driving control unit 84 can be realized by cooperation of hardware such as a processor and software that causes the hardware to operate.

The driving mode selection unit 82 selects, as the driving mode of the autonomous vehicle 10, any one of the automatic driving mode, the semi-automatic driving mode, and the manual driving mode. Specifically, the driving mode selection unit 82 selects the driving mode of the autonomous vehicle 10 based on the driving mode change instruction that has been input to the touch panel 28 by the operator. The driving mode selected by the driving mode selection unit 82 is notified to the driving control unit 84.

The driving control unit 84 performs driving control for the autonomous vehicle 10 based on an instruction input from the touch panel 28, the emergency-stop operation unit 34, or the mechanical operation unit 70.

Specifically, upon receiving the start instruction from the touch panel 28 when the GO button 40 (see FIG. 4 ) of the touch panel 28 is touched, the driving control unit 84 releases the motor-driven parking brake and controls the prime mover to cause the autonomous vehicle 10 to start traveling. Further, upon receiving the deceleration control instruction from the touch panel 28 when the SLOWDOWN button 42 (see FIG. 5 ) of the touch panel 28 is touched, the driving control unit 84 controls the prime mover and the brake to cause the autonomous vehicle 10 to decelerate.

When the mechanical operation unit 70 is tilted forward, the driving control unit 84 controls the prime mover to accelerate the autonomous vehicle 10 upon receiving the acceleration control instruction from the mechanical operation unit 70. Further, when the mechanical operation unit 70 is tilted rearward, the driving control unit 84 controls the prime mover or the brake to cause the autonomous vehicle 10 to decelerate upon receiving the deceleration control instruction from the mechanical operation unit 70. Further, when the mechanical operation unit 70 is tilted leftward, the driving control unit 84 controls the directions of the wheels 14 of the autonomous vehicle 10 to cause the autonomous vehicle 10 to turn left upon receiving the left-turn control instruction from the mechanical operation unit 70. When the mechanical operation unit 70 is tilted rightward, the driving control unit 84 controls the directions of the wheels 14 of the autonomous vehicle 10 to cause the autonomous vehicle 10 to turn right upon receiving the right-turn control instruction from the mechanical operation unit 70.

Further, when the emergency-stop operation unit 34 is operated, the driving control unit 84 controls the prime mover and the brake to cause the autonomous vehicle 10 to stop immediately upon receiving the stop instruction from the emergency-stop operation unit 34.

In the case of operation in the automatic driving mode, the driving control unit 84 performs driving control for the autonomous vehicle 10 based on driving instructions received from the management center. Further, in the case of operation in the semi-automatic driving mode, the driving control unit 84 performs driving control for the autonomous vehicle 10 based on detection results by various sensors of the autonomous vehicle 10.

As mentioned above, the driving control unit 84 executes the driving control including the vehicle speed control for the autonomous vehicle 10. Accordingly, the driving control unit 84 functions as a vehicle speed control unit, and the driving control device 80 functions as a vehicle speed control device.

Irrespective of the driving mode of the autonomous vehicle 10, the driving control unit 84 can perform driving control for the autonomous vehicle 10 based on driving control instructions from the touch panel 28 and the mechanical operation unit 70. However, when the driving mode of the autonomous vehicle 10 is either the automatic driving mode or the semi-automatic driving mode, the driving control unit 84 prioritizes a vehicle speed control instruction input from the touch panel 28 over a vehicle speed control instruction input from the mechanical operation unit 70 and executes the vehicle speed control for the autonomous vehicle 10 based on the prioritized instruction.

For example, prioritizing the vehicle speed control instruction input from the touch panel 28 in the automatic driving mode or the semi-automatic driving mode invalidates the vehicle speed control instruction input from the mechanical operation unit 70, after the vehicle speed control instruction is input by the touch panel 28, until the driving control unit 84 completes the vehicle speed control. Specifically, when the SLOWDOWN button 42 of the touch panel 28 is touched, the driving control unit 84 ignores the acceleration control instruction from the mechanical operation unit 70 and causes the autonomous vehicle 10 to decelerate, until the driving control unit 84 completes the deceleration control, even when the mechanical operation unit 70 is tilted forward.

Alternatively, in the case of operation in the automatic driving mode or the semi-automatic driving mode, the vehicle speed control instruction from the touch panel 28 may be prioritized by not receiving any vehicle speed control instruction from the mechanical operation unit 70. In this case, in the automatic driving mode or the semi-automatic driving mode, any vehicle speed control instruction from the mechanical operation unit 70 is invalidated, regardless of whether the operator is operating the touch panel 28.

In the case of operation in the automatic driving mode, the driving control unit 84 performs driving control for the autonomous vehicle 10 based on driving instructions from the management center. However, the vehicle speed control instructions from the touch panel 28 and the mechanical operation unit 70 are prioritized over the vehicle speed control instructions from the management center. Further, in the case of operation in the semi-automatic driving mode, the driving control unit 84 performs driving control for the autonomous vehicle 10 based on detection results by various sensors of the autonomous vehicle 10. However, the vehicle speed control instructions from the touch panel 28 and the mechanical operation unit 70 are prioritized over the vehicle speed control instructions based on detection results of various sensors.

As described above, in the present embodiment, the vehicle speed control instructions input from the touch panel 28 are prioritized over the vehicle speed control instructions input from the mechanical operation unit 70 in the automatic driving mode. Therefore, even when the mechanical operation unit 70 is unwantedly operated by the operator or another occupant while the operator is performing vehicle speed control using the touch panel 28, performance of any vehicle speed control not intended by the operator can be suppressed. Further, prioritizing the vehicle speed control instructions from the touch panel 28 impels the operator to mainly operate the touch panel 28, in the case of operation in the automatic driving mode. Therefore, the operator can easily grasp information displayed on the touch panel (for example, vehicle information, environmental information, and external messages).

When the driving mode of the autonomous vehicle 10 is the manual driving mode, the driving control unit 84 may prioritize the vehicle speed control instructions input from the mechanical operation unit 70 over the vehicle speed control instructions input from the touch panel 28 and execute the vehicle speed control for the autonomous vehicle 10 based on the prioritized instructions. For example, in the manual driving mode, after the mechanical operation unit 70 inputs a vehicle speed control instruction, until the driving control unit 84 completes the vehicle speed control, any vehicle speed control instruction input from the touch panel 28 may be invalidated.

In addition, irrespective of the driving mode of the autonomous vehicle 10, the driving control unit 84 prioritizes the stop instruction input from the emergency-stop operation unit 34 over the vehicle speed control instructions input from the touch panel 28 and the mechanical operation unit 70 and causes the autonomous vehicle 10 to stop immediately. Needless to say, the stop instruction input from the emergency-stop operation unit 34 is prioritized over the vehicle speed control instructions from the management center and the vehicle speed control instruction based on detection results by various sensors of the autonomous vehicle 10. That is, regardless of the driving mode of the autonomous vehicle 10, and regardless of how the touch panel 28 or the mechanical operation unit 70 is operated, the autonomous vehicle 10 immediately stops when the emergency-stop operation unit 34 is operated. Thus, the operator can stop the autonomous vehicle 10 at any time in an emergency.

Although the embodiments of the autonomous vehicle speed control device according to the present disclosure have been described, the autonomous vehicle speed control device according to the present disclosure is not limited to the above-mentioned embodiments and can be changed or modified in various ways without departing from the gist thereof. 

The invention claimed is:
 1. An autonomous vehicle speed control device provided in an autonomous vehicle capable of driving in a plurality of modes including an automatic driving mode for performing automatic driving, comprising: a touch panel on which a vehicle speed control button for inputting a first vehicle speed control instruction to the autonomous vehicle is displayed; a joystick provided higher than a seat surface of a seat of the autonomous vehicle and configured to input a plurality of different control instructions, the different control instructions including at least a second vehicle speed control instruction, a device control instruction, and a turn control instruction, to the autonomous vehicle by manual operation; and a processor configured to (i) control the autonomous vehicle based on at least one of the different control instructions irrespective of the mode of the autonomous vehicle when an operator is not inputting the first vehicle speed control instruction in the automatic driving mode and the processor is not executing the first vehicle speed control instruction in the automatic driving mode and (ii) control a vehicle speed of the autonomous vehicle by prioritizing the first vehicle speed control instruction input from the touch panel over the second vehicle speed control instruction input from the joystick, in the automatic driving mode.
 2. The autonomous vehicle speed control device according to claim 1, further comprising: a mechanical emergency-stop button for inputting a stop instruction to the autonomous vehicle, wherein the processor causes the autonomous vehicle to stop by prioritizing the stop instruction input from the mechanical emergency-stop button over the first vehicle speed control instruction input from the touch panel and the second vehicle speed control instruction input from the joystick.
 3. The autonomous vehicle speed control device according to claim 1, wherein in the automatic driving mode, the processor prioritizes a deceleration control instruction input from the touch panel over the second vehicle speed control instruction input from the joystick and causes the autonomous vehicle to decelerate.
 4. The autonomous vehicle speed control device according to claim 1, wherein the joystick can be stored in a storage compartment covered with a lid.
 5. The autonomous vehicle speed control device according to claim 1, wherein in the automatic driving mode, the processor invalidates the second vehicle speed control instruction from the joystick when prioritizing the first vehicle speed control instruction input from the touch panel over the second vehicle speed control instruction input from the joystick.
 6. The autonomous vehicle speed control device according to claim 1, wherein a foot-operated pedal for inputting a third vehicle speed control instruction to the autonomous vehicle is not provided.
 7. The autonomous vehicle speed control device according to claim 1, wherein the prioritizing, by the processor, of the first vehicle speed control instruction input from the touch panel over the second vehicle speed control instruction input from the joystick occurs when the operator is inputting the first vehicle speed control instruction in the automatic driving mode or the processor is executing the first vehicle speed control instruction in the automatic driving mode. 